2,307 research outputs found
Putting medical devices in context: a systematic review of evidence on design targeting low-resource settings
Most medical devices are inaccessible to healthcare facilities in low-resource settings (LRSs), severely limiting medical care for a vast proportion of the world's population. This article characterises the process used for designing medical devices for LRSs and investigate how the context-of-use is integrated into the process. A systematic review of 64 papers was conducted to identify peer-reviewed studies of devices intended for LRSs. Using the biodesign process as an analytic framework, a qualitative meta-analysis was conducted. Findings show the studies predominantly describe the later stages of medical device design, whilst largely neglecting how knowledge of the context is considered. To support engineers and improve outcomes, it is imperative that an understanding of the context is integrated throughout the design and product development process. This article highlights this gap and hopes to stimulate research into how context can be better incorporated into the design process for medical devices targeting those populations most in need.This is the author accepted manuscript. The final version is available from Inderscience Publishers via http://dx.doi.org/10.1504/IJDE.2015.07637
Model for coiling and meandering instability of viscous threads
A numerical model is presented to describe both the transient and
steady-state dynamics of viscous threads falling onto a plane. The steady-state
coiling frequency w is calculated as a function of fall height H. In the case
of weak gravity, w ~ H^{-1} and w ~ H are obtained for lower and higher fall
heights respectively. When the effect of gravity is significant, the relation w
~ H^2 is observed. These results agree with the scaling laws previously
predicted. The critical Reynolds number for coil-uncoil transition is
discussed. When the gravity is weak, the transition occurs with hysteresis
effects. If the plane moves horizontally at a constant speed, a variety of
meandering oscillation modes can be observed experimentally. The present model
also can describe this phenomenon. The numerically obtained state diagram for
the meandering modes qualitatively agrees with the experiment.Comment: 12 pages, 10 figure
The diagnostic accuracy and cost-effectiveness of magnetic resonance spectroscopy and enhanced magnetic resonance imaging techniques in aiding the localisation of prostate abnormalities for biopsy : a systematic review and economic evaluation
Peer reviewedPublisher PD
Evaluation of SIP Signalling and QoS for VoIP over OLSR MANET Routing Protocol
Abstract:
This paper evaluates the SIP based VoIP applications over the Optimized Link State Routing protocol (OLSR) as a proactive routing protocol for Mobile Ad Hoc Networks (MANET) using Static, Uniform, and Random mobility models. The evaluation considered PCM, LQS, IPTelephony, and GSM voice codecs to study the SIP signaling performance and the voice Quality of Service (QoS) for VoIP calls over OLSR MANET. The simulation efforts performed in OPNET Modeler 17.1. The results show that VoIP over OLSR MANET has good performance over Static and Uniform mobility models while it has variable performance with Random models. SIP signaling has large delays compared with the voice signaling which reduce the VoIP performance and increases the call's duration. In addition, GSM and LQS based VoIP calls have an acceptable level of QoS while PCM and IP-Telephony based VoIP calls have a low level of QoS over different types of mobility models. Furthermore, the location and the mobility of SIP server affect the number of hops and the SIP signaling performance between the different parties of the VoIP call
Blaming Bill Gates AGAIN! Misuse, overuse and misunderstanding of performance data in sport
Recently in Sport, Education and Society, Williams and Manley (2014) argued against the heavy reliance on technology in professional Rugby Union and elite sport in general. In summary, technology is presented as an elitist, ‘gold standard’ villain that management and coaches use to exert control and by which players lose autonomy, identity, motivation, social interactions and expertise. In this article we suggest that the sociological interpretations and implications offered by Williams and Manley may be somewhat limited when viewed in isolation. In doing so, we identify some core methodological issues in Williams and Manley’s study and critically consider important arguments for utilising technology; notably, to inform coach decision making and generate player empowerment. Secondly, we present a different, yet perhaps equally concerning, practice-oriented interpretation of the same results but from alternative coaching and expertise literature. Accordingly, we suggest that Williams and Manley have perhaps raised their alarm prematurely, inappropriately and on somewhat shaky foundations. We also hope to stimulate others to consider contrary positions, or at least to think about this topic in greater detail. More specifically, we encourage coaches and academics to think carefully about what technology is employed, how and why, and then the means by which these decisions are discussed with and, preferably, sold to players. Certainly, technology can significantly enhance coach decision making and practice, while also helping players to optimise their focus, empowerment and independence in knowing how to achieve their personal and collective goals
The Birmingham Boron Neutron Capture Therapy (BNCT) project : developments towards selective internal particle therapy
This paper will review progress on two aspects of the Birmingham BNCT project. Firstly on evaluation of the effects of high and low LET radiations when delivered simultaneously, and secondly on attempts to optimise delivery of the boron carrier compound BPA through pharmacokinetic studies. Simultaneous or non-simultaneous irradiations of V79 cells with alpha-particle and X-ray irradiations were performed. Alpha doses of 2 and 2.5 Gy were chosen and the impact on survival when delivered separately or simultaneously with variable doses of X-rays was evaluated. The pharmacokinetics of the delivery of a new formulation of BPA (BPA-mannitol) are being investigated in brain tumour patients through a study with 2 × 2 design featuring intravenous and intracarotid artery infusion of BPA, with or without a mannitol bolus. On the combined effect of low and high LET radiations, a synergistic effect was observed when alpha and X-ray doses are delivered simultaneously. The effect is only present at the 2.5 Gy alpha dose and is a very substantial effect on both the shape of the survival curve and the level of cell killing. This indicates that the alpha component may have the effect of inhibiting the repair of damage from the low LET radiation dose delivered simultaneously. On the pharmacokinetics of BPA, data on the first three cohorts indicate that bioavailability of BPA in brain ECF is increased substantially through the addition of a mannitol bolus, as well as by the use of intracarotid artery route of infusion. In both cases, for some patients the levels after infusion approach those seen in blood, whereas the ECF levels for intravenous infusion without mannitol are typically less than 10% of the blood values
Culture change in elite sport performance teams: Examining and advancing effectiveness in the new era
Reflecting the importance of optimizing culture for elite teams, Fletcher and Arnold (2011) recently suggested the need for expertise in culture change. Acknowledging the dearth of literature on the specific process, however, the potential effectiveness of practitioners in this area is unknown. The present paper examines the activity's precise demands and the validity of understanding in sport psychology and organizational research to support its delivery. Recognizing that sport psychologists are being increasingly utilized by elite team management, initial evidence-based guidelines are presented. Finally, to stimulate the development of ecologically valid, practically meaningful knowledge, the paper identifies a number of future research directions
Reduction of low- and high-grade cervical abnormalities associated with high uptake of the HPV bivalent vaccine in Scotland
In Scotland, a national HPV immunisation programme began in 2008 for 12-13 year olds, with a catch-up campaign from 2008-2011 for those under the age of 18. To monitor the impact of HPV immunisation on cervical disease at the population level, a programme of national surveillance was established. We analysed colposcopy data from a cohort of women born between 1988-1992 who entered the Scottish Cervical Screening Programme (SCSP) and were aged 20-21 in 2008-2012. By linking datasets from the SCSP and colposcopy services, we observed a significant reduction in diagnoses of cervical intraepithelial neoplasia 1 (CIN 1) (RR 0.71, 95% CI 0.58 to 0.87, p=0.0008), CIN 2 (RR 0.5, 95% CI 0.4, 0.63, p<0.0001) and CIN 3 (RR 0.45, 95% CI 0.35 to 0.58, p< 0.0001) for women who received 3 doses of vaccine compared with unvaccinated women. To our knowledge, this is one of the first studies to show a reduction of low and high grade cervical intraepithelial neoplasia associated with high uptake of the HPV bivalent vaccine at the population level. These data are very encouraging for countries that have achieved high HPV vaccine uptake
Hydrophobic gating of mechanosensitive channel of large conductance evidenced by single-subunit resolution
Mechanosensitive (MS) ion channels are membrane proteins that detect and respond to membrane tension in all branches of life. In bacteria, MS channels prevent cells from lysing upon sudden hypoosmotic shock by opening and releasing solutes and water. Despite the importance of MS channels and ongoing efforts to explain their functioning, the molecular mechanism of MS channel gating remains elusive and controversial. Here we report a method that allows single-subunit resolution for manipulating and monitoring “mechanosensitive channel of large conductance” from Escherichia coli. We gradually changed the hydrophobicity of the pore constriction in this homopentameric protein by modifying a critical pore residue one subunit at a time. Our experimental results suggest that both channel opening and closing are initiated by the transmembrane 1 helix of a single subunit and that the participation of each of the five identical subunits in the structural transitions between the closed and open states is asymmetrical. Such a minimal change in the pore environment seems ideal for a fast and energy-efficient response to changes in the membrane tension.
Experiencing a first food allergic reaction: a survey of parent and caregiver perspectives
BACKGROUND: Insufficient knowledge of food allergy and anaphylaxis has been identified by caregivers as an important barrier to coping, and a potential cause of fear and anxiety, particularly for those with children newly diagnosed with food allergy. The purpose of the study was to better understand the experiences of caregivers of children with a first allergic reaction to food, and to identify any deficiencies in the information received at diagnosis. METHODS: A mixed-methods study consisting of an online survey administered to the Anaphylaxis Canada online registry (a patient support group database of approximately 10,000 members), and a follow-up qualitative interview with a subset of survey participants. Analysis consisted of frequency analysis (quantitative and qualitative data) and descriptive statistics to calculate proportions and means with standard deviations. Qualitative analyses were guided by the constant comparative method of grounded theory methodology. RESULTS: Of 293 survey respondents, 208 were eligible to complete the survey (first allergic reaction to food within 12 months of the study), and 184 respondents consented. Identified gaps included education about food allergy, anaphylaxis management, for example, how to use epinephrine auto- injectors, and coping strategies for fear and anxiety. The qualitative follow-up study supported these findings, yielding 3 major themes: 1) lack of provision of information following the episode on the recognition and management of food allergy related allergic reactions, 2) prolonged wait times for an allergist, and 3) significant family anxiety. CONCLUSIONS: The online survey highlighted multiple deficiencies at diagnosis, findings which were supported by the follow up qualitative study. Results will inform the development of educational strategies for patients newly diagnosed with food allergy
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